function open_win(page,wid,hei) { // otevre nove okno s obrazkem
nove_okno = window.open(page,'image','width='+wid+',height='+hei+',alwaysLowered=0,alwaysRaised=0,channelmode=0,dependent=1,directories=0,fullscreen=0,hotkeys=1,location=0,menubar=0,resizable=0,scrollbars=1,status=0,titlebar=0,toolbar=0,z-lock=0,screenX=0,screeny=0,left=20,top=20');
}
function setImage(name, new_src, layer)
{
	// version test
	if ((navigator.appName == 'Netscape' && parseFloat(navigator.appVersion) >= 3) ||
		(parseFloat(navigator.appVersion) >= 4)
	) {
		if (!document.layers || !layer)
			eval('document.' + name + '.src = "' + new_src + '"');
		else
			document.layers[layer].document.images[name].src = new_src;
	};
}


var layer_timer = 0;
var layer_stack = new Array();

function setLayerVisible(name, visible, image_name, image_data)
{
	var layer = document.layers?document.layers[name]:document.all?document.all[name]:document.getElementById(name);

	// hide stacked layers
	while ((layer_stack.length > 1) && ((visible == -1) || ((visible == 1) && (layer_stack[layer_stack.length - 2] != name)))) {
		// if stacked layer is picture (data part is not empty)
		if (layer_stack[layer_stack.length - 1] != "") {
			setImage(
				layer_stack[layer_stack.length - 2],
				layer_stack[layer_stack.length - 1],
				(layer_stack.length > 3)?layer_stack[layer_stack.length - 4]:""
			);
			layer_stack.length -= 2;
		} else setLayerVisible(layer_stack[layer_stack.length - 2], -2);
	};
	
	switch (visible) {
	case 1:
	case 2:
		clearTimeout(layer_timer);

		// push layer
		if (layer_stack[layer_stack.length - 2] != name) {
			// store image first if defined
			if (image_name) {
				layer_stack[layer_stack.length] = image_name;
				layer_stack[layer_stack.length] = image_data;
			};
			
			layer_stack[layer_stack.length] = name;
			layer_stack[layer_stack.length] = "";
		};

		// show layer
		if (!layer) return;
		if (document.layers) layer.visibility = "show";
		else layer.style.visibility = "visible";
		break;
	case 0:
		// set hide timer to 0.5 second
		clearTimeout(layer_timer);
		layer_timer = setTimeout("setLayerVisible('" + name + "', -1)", 500);
		break;
	default:
		// remove layer from stack
		if (layer_stack.length > 1) layer_stack.length -= 2;
		else layer_stack.length = 0;

		// hide layer
		if (!layer) return;
		if (document.layers) layer.visibility = "hide";
		else layer.style.visibility = "hidden";
		break;
	}; // switch (visible)
} // function setLayerVisible(name, visible, image_name, image_data)